System of vertical differential ventilation



,Oct. 30,1928.-

- A. KNAPEN SYSTEM OF VERTICAL DIFFERENTIAL VENTILATION mta 1 Patented30, .1928.

UNITED STATES.

PATENTBFFICE.

AGHILLE-KNAPEN, or BRUSSELS, BELGIUM.

SYSTEM OF V'ERTICAL DIFFERENTIAL VENTILATION.

Application filed January 29, 1927, Serial No. 164,496. and in BelgiumJanuary 30, 1926.

My invention relates to a system for vertical differential ventilationWlllCll 1s adapted to be used in order to renew the air in anysubstantially Closed chamber by continuous exchange, whatever may be thetemperatureinside or outside the rooms which are to be ventilated,'thenature, the position, or the area of the said chambers whether they besituated under the level of the ground, under the level of the Water, orabove this level such as it may be the case in ships, undergroundtunnels and the like, and more especially when it is not possible toreach the outer atmosphere in the horizontal'direction.

My process is essentially based on the cooperation of ducts or chimneyswhich are any other suitable form in order to produce by a-chimney of arelatively greater section and of a relatively smaller length, a quickescapement of the light air which is sto ped under pressure against theceiling o the room, and to obtain through the chimneys or ducts, of arelatively greater length and-of a smaller section, opening at differentlevels above the ground, an introduction of fresh am into the room oreventually an introduction of fresh air and an escapem'ent of air,

in cooperation with'the chimney or duct arranged under the ceiling.

In order to explain the invention more 'fully it will bedescribdhereinafter with reference to the annexed drawing in which- Fig. 1 is alongitudinal section of a room,

,.Whl0h is supposed to be an underground room without directcommunication with the outer atmosphere in the horizontal direction2inFi 1.

Fig. 3 1s a.- similar cross section taken through line H in Fig. 1 andFig. 4 is a crom section taken through line HinEigL 'In the .procemes ofvertical ventilation which have heretofore been used and which are basedon the principles of Reckmagel, S er and. other experts in'the art, theescapethe heating during the winter.

ment of the air from the rooms or other places lscaused by theutilization of ducts or chimneys in each room to be ventilated, eachroom having an inlet port or opening and an outlet port connecting theroom to the free air at a certain height above the roomor place to beventilated.

Experiments have shown that, when the depression in such a ductorchimney exceeds a givenlimit, its sucking action is transmit-- teddirectly through the atmosphere of the room to the outer air through thefissures or the joints of the doors and windows or through an inlet portleading to a connecting stalrway provided for this purpose at "the'level ofthe floor or pavement. In such a systerm the outer air, suckedin through the port,

or the fissures, or'the joints of the doors and windows passes at fullspeed as a projectile,

in producmg a blow of air, the trajectory of which is the shortestdistance between the fissures or the like and the'duct. The greater thedepression in the duct, the more bent is the trajectory of this blow ofair. This displacement of air at a great speed has no effect on theventilation or on-the renewal of the greater portion of air in the roomor place which is ventilated in this way. *In summer, when the outertemperature has reached a certain degree, the'column of air contained inthe duct'or chimney, being more dense (because it is less hot, than theouter air and being no more-supported at the intenor inlet port underthe ceiling, by layers of air having a density equal to its density,descends and tends to escape to the outside in followingthe way of lessresistance and in stretching in layers on the floor.

From the point of view of the exchange of the air in the roomsor'places, such a natural vertical inverted-ventilation is noteflicacious, being rather injurious, because it attracts the smells ofsoot in the rooms or places together with the dusts which haveaccumulated by In under ground places or rooms which are surrounded onall sides by walls, this system of vertical ventilation is'notoperative.

' These drawbacks are overcome by means of the system-forming thesubject matter of m invention which is based, in order to ventilate aplace or roomS, surrounded on all sides by" walls 9 o'r built'in theground, or enclosed in the shell of a vessel, on the cooperation ofducts, or' chimneys of difierent sections and ofdifierent lengths andconnecting theinte rior of each chamber to be ventilated to the outsideatmosphere.

In the example shown, the system comprises ajductf of relativel greatersection and shorter length but, su cient in order to put in directcontact, through the shortest. way,

'the light air, accumulatedunder pressure against the ceili'ng 11-, withthe outer air, inorder to allow its es'capement as quickly as ossibleand also with the least'resistance.

, shown on Fig. 2, this chimney 10 opens byan inlet 12 just underthe'ceiling 11, passes into the 'wa1l.13 and opens by a port 14 in at 2or 3 meters a ove the ground according the outer air at the level of theterrace 15, the 'port 14 being directed either towards the terrace asshown or any' other desired direction. With this chimney or duct 10,cooperatesa'chimney 16 of relatively smaller section and ofgreater'length. The lower port 17 of this chimney descends to a givendistance 18 above the ground 19, for example to a distance of about 60cm.

This port 17 may ho'wever'be arranged in certain case's'at a eaterheight, .for instance to the places or rooms to be ventilated.

The chimney 16, contrarily to what is the case with regard to the duct10, is used for vbeu - of the .chimney :16.

the introduction of fresh air by difference of density and of volume. Tothis end, it opens 'in the outer air, at 20, as shown in Fig. 3.

The system may comprise a third chimney or duct 21 the section of whichis still smaller than the section of the chimney 16 and opens, through aport 22 at a distance 23 above the oundthis distance being differentfrom the istance between the outer air at 24 is used for theintroductionof fresh air, if, in consequence ota difference of tem erature, thechimney or duct 16 would sed for a moment, for the escapement of air incooperation with the chimney 10. j

' The sections of the chimneys or ducts 10,,

' 16 and 21 bein in predetermined proportions, their com in'ed actionresults in complete ventilation through the continuous exchange of aircaused thereby regardless of the level orvolume of the room beingventilated.-

.Without the proper cooperation of the various ducts the equality of theair in the chimneys or ducts would notexist and complete ventilationcould not be obtained.

The described system has many advantages fro'mthe pointof view of thevrenewal of'the air by continuous ex'chan s, whatever may 1 flbegthe,(temperature "insi to reach the outerfatm s I r e or outside the placesaneomsfmm wh ch it isnot possible direction,i -such,as inc arsptunnels,ships, and other buildin -i .It may also used with success to ventilatethe interiors of bujldings of great volumein which the ventilation oundand the port 17 n'this case, the third 'chimne' o'r' duct 21 whichopensalso in the here in horizontal is secured b the system ofdifierential horizontal ventilation, and in which apertures are used forthe" introduction of air, these apertures being arranged with differentaspects in the walls of a building and cooperating with apertures forthe passage of air in the separating walls of places or rooms situatedon the same level. 'In this case, indeed,

itmay happen that on account of the great dimension of the places orrooms, a'sto per of inert air is formed in the middle 0 the aerialvolume to be renewed; 'in this case the above described system willremove the inertia of the stopper thus producing a kind of ventilationrelay.

Similarly, in movable enclosures, such as railways, carriages, motorvehlcles, runmng at a great speed, the immobility of the inner air isdue to the sliding along the walls of the outer inert atmosphere whichacts as a barrier at the inlet and at the outlet when there is nolateral additional pressure of the wind. The same condition results atthe chimney. When the speed of the surrounding air isgreater than thetension of the warm port of a.

gases discharged from the chimney, as in warm gases is prevented by thesurrounding air and there is a flow back through the chin ney. In theinstance of a movin vehicle, the

1 some instances, the complete escape of the J speed of thevehicle'increases t e inertia of the air and renders it relatively rigidand when the atmosphere is very warm the trans- I which are fit intorecesses or which, are disposed under the ground and which have nolateral contact with the outer atmosphere; in consequence, it may beused for the ventilation of ships, tunnels, cellars, undergrounds,

and the'li ke. In each case, and according to the characterof the placesor .rooms, a num-.

ber of similar elements of ventilation may be used, each comprising onthe minimum two or a greater. number'of ducts or chimneys oi dlflerentsections and of different lengths.

What I claim is:

1. In a system for the ventilation ofa chamber or the like, asubstantially verticalduct connecting the upper portion of said chamberwith the external atmosphere where'- bythe upper strata of air in saidchamber may pass upwardly and outwardly, and a second duct of relativelysmaller cross section and longer length than said first mentioned duct,

connecting the-lower portion of said chamber with. theatmosphere whereby air from the exterior may flow downwarcLy and into League v 3 a saidchamber thus ca'usin a oontinuons flow other oductsisuccessively smallerin diameter of air through said chamfiw r. j 2. In a system for theventilation of a connecting successively lower-portions of said chamberorfthe'like, a substantiallyvertical chamber to the external atmospherewhereby I ductconne'ctjing the. upper portion of. said air' may passintosaid chamber to cause a chamber witht eexternal atmospherewherecontinuouschange of airtherein.

by the upper, strata of'a'ir' in -'s'aid-chamber and longer than saidfirst mentioned duct and y I may escapetothe'ex terior and'aplmrality'oi H I i

